Countdown to training camp: One in a series previewing the Browns’ roster leading up to the opening of training camp on July 25.

Position: Running back.

Quick overview: Although the offense espoused by coach Rob Chudzinski and coordinator Norv Turner is known for its vertical-strike passing game, the foundation essentially is a power running attack. Turner’s coaching roots lie with John Robinson’s power-running teams at USC and the old Los Angeles Rams. When Chudzinski oversaw the most productive Browns offense in 30 years in 2007, Jamal Lewis rushed for 1,304 yards. Lewis’ 298 carries (he missed one game) ranks No. 3 on the club’s all-time season list and only Jim Brown had more yards in a season in franchise history.

Analysis: One of the first things Turner said to Richardson upon meeting him was, “You know I had Emmitt Smith.” Smith, who preceded Richardson as a football hero in Pensacola, Fla., won three of his four NFL rushing titles in Dallas with Turner as Cowboys coordinator. He also averaged 55 catches a season. The Browns kept Richardson out of about one-half the OTA and minicamp practices because of a pulled muscle in a lower leg. Club doctors feared the injury might lead to a stress fracture, so they shut him down. Backs under Turner average about 300 carries and 55 catches in a season, so Richardson has to stay healthy for the offense to work.

Don’t be surprised if: Montario Hardesty loses his roster spot. Turner’s backs have to be able to catch the ball. Hardesty is a hard runner who has overcome numerous knee injuries and survived two head coaches. Through it all, he has been a liability as a dump-off receiver out of the backfield.

Key questions: 1. Can Marecic, the only natural lead-blocker on the roster, retain the fullback position despite a poor 2012, or will the coaches accommodate the position through a combination of Ogbonnaya and a tight end, or with Smelley? 2. Can Ogbonnay or the 5-6 ½ Lewis be counted on to ably replace Richardson in the event of another injury to the feature back?

Fun fact: Three running backs on teams Turner has coached have captured a total of five NFL rushing titles.